1. Field of the Invention
The present invention generally relates to a board lock for securing an electrical to a substrate, and in particular to a universal board lock which is capable of securing an electrical connector to substrates of different thicknesses.
2. The Prior Art
An electrical circuit usually comprises a printed circuit board on which a plurality of electrical elements and devices are mounted. Some of the electrical elements are fixed to the circuit board by means of external fasteners or board locks before they are soldered to the circuit board. Examples of board locks are shown in Taiwan Patent Application Nos. 84101384, 83112290, 85207102, and 86201142.
FIG. 5 of the attached drawings shows a conventional board lock 5. The board lock 5 comprises an expanded end 51 from which a pair of resilient legs 52 extend in an axial direction. Each of the resilient legs 52 has a barb 521 formed on a free end thereof.
The board lock 5 is received in a bore 61 defined in an electrical device 6 and supported in the bore 61 with the legs 52 extending through a narrow section of the bore 61. The legs 52 are received in a hole 21 defined in a circuit board 2. The free ends of the legs 52 extend through the hole 21 and the barbs 521 engage with a bottom face of the circuit board thereby securing the electrical device 6 to the circuit board 2.
The securing of the electrical device 6 to the circuit board 2 is basically provided by the engagement between the barbs 521 and the bottom face of the circuit board 2. This implies that the axial dimension of the legs 52 has to substantially correspond to the thickness of the circuit board 2 in order to ensure that the electrical device 6 is effectively secured to the circuit board 2. A disadvantage associated with this is that different board locks must be used with circuit boards of different thicknesses.
It is thus desirable to have a universal board lock that allows an electrical device to be effectively secured to substrates of different thicknesses.